OK...I hope you will pardon my complete ignorance. I've not ever really worked on the the rear end of any of my Mopars (insert any of several jokes here). So, I'm a complete newbie. I'll tell you what I know, what I have, and what I'm looking at purchasing. The things I worry about are the things that I don't know that I don't know.

I have a B-body 8.75 that I will use on my 68 Barracuda. Currently, it is just the housing with no pig/chunk/pumpkin in it. I have also run across a 742 chunk to put in it. Its got a Detroit Locker in it and 5.00+ gears that came from an early 70's NASCAR shop. They are in very good (like new) condition based on the seller's info and I know him from other dealings and he's trustworthy. I'm not all that interested in that gearing. But, I know I can change that out for what I want. That's all I know about it. And, I think there are more things I need to know. But, I'm not sure what to ask.

1. Will I need to find out how many splines the set up supports? Or is it a standard deal for all 742's?

2. Should I count the splines on the axles I have currently and see if it will match what this 742 has?

3. Does anyone sell an offset shackle for the A-body (I only need a 1/2 inch offset each side)?

4. Any idea if these older Detroit Lockers would be the same as today (ie would parts be a problem if something happened)? Any idea of what they might be worth?

1. All 8 3/4" Detroit Lockers are 30 spline.
2. All stock 8 3/4" rears are 30 spline.
3. I make a 1/2" offset A-body spring hanger/shackle kit.
4. Vintage Detroit Lockers are not the same as new ones.
5. New Detroit Lockers run run about $550.

Thanks for the answers.

A followup....
The guy is asking $650 for these 742's with the older Detroits in them. So I can get a new Detroit for $550. But, that doesn't include the case and the like. All I should have to do with these is change out the ring and pinion and install.So, its hard to compare. I worry about them being the older models and all. Do you think this is a valid concern? Then again, I have my doubts that I'd ever be able to kill them with what I'm planning on running.

Any thoughts on if this is a good deal or not?

I would pass.

You can buy a core 742 case for $100, so the price is about the same.

So, I figure the breakeven on this is around $300-400?